Hat accessory



FIG. 1 is a perspective view of a hat accessory showing my new design;

FIG. 2 is a top view thereof;

FIG. 3 is a side view thereof;

FIG. 4 is a front view thereof;

FIG. 5 is a rear view thereof; and,

FIG. 6 is a perspective view, showing the claimed design in use.

The broken lines in FIGS. 1 and 4, which define the bounds of the claimed design, form no part thereof. The broken line showing of the baseball-style cap in FIG. 6 illustrates environmental matter and forms no part of the claimed design. 

The ornamental design for a hat accessory, as shown and described. 